Passenger perception of vehicle occupancy in public transport and factors that shape crowding estimations

This study explores the subjective estimation of vehicle occupancy (SEVO) in public passenger transport (PPT), with a focus on demographic, situational, and environmental factors. Addressing a gap in research within Southeastern Europe, the analysis is based on onboard survey data collected during travel survey data from 1,318 passengers on two high-demand urban bus lines in Novi Sad, Serbia. The results show that SEVO is significantly influenced by time of day (peak vs. off-peak), seat and space availability, passenger position (standing vs. seated), comfort level, age, noise, perceived overcrowding, time inefficiency, injury risk, and professional status. In contrast, variables such as travel time, smell, security perception, frequency of PPT use, and trip purpose did not yield statistically significant effects. Notably, passengers standing at the back perceived significantly higher occupancy than those at the front, and lower comfort ratings were associated with higher SEVO. These findings suggest that perceived crowding depends not only on actual occupancy but also on spatial position and individual comfort. The study highlights the importance of integrating subjective assessments into transport planning and decision-making. Future research should combine subjective perceptions with objective metrics such as vehicle load and stress indicators to create more comprehensive models for improving public transport efficiency and user satisfaction.